- Détails du magazine
- Première publication
- 01 Jan 1992
- Période de publication
- 4 fois par an
- Accès libre
Gas Chromatographic Determination of Insecticide Residues in Dried and Fermented Tobacco Samples of Field Trials and Vegetation Studies/Gaschromatographische Bestimmung von Insektizid-Rückständen an getrockneten und fermentierten Tabakproben aus Feld- und Vegetationsversuchen
Pages: 201 - 206
From the chlorinated hydrocarbons aldrin and heptachlor, applied to the soil for the control of insects, no aldrin or heptachlor could be found in the tobacco leaves. Small quantities of dieldrin (0.01-0.09 ppm) and heptachlor epoxide (0.28-3.5 ppm) were, however, detected. The roots contained remarkable quantities of aldrin and dieldrin, heptachlor I + II + III, and heptachlor epoxide. Other metabolites were not found in tobacco. If lindane was applied to the soil only traces of this insecticide (0.01.-0.16 ppm) were taken up by the tobacco plants and could be identified in the lower and upper leaves. On application after transplanting, aldrin (0.3-3.6 ppm) and heptachlor I + II and heptachlor epoxide (0.1-28 ppm) were found in the middle and top leaves. From the insecticides of organic phosphorous compounds (parathion, metasystox, malathion and bromophos) usually no residues could be found in air-cured tobacco when they were applied 2 weeks before harvesting. On tobacco with high content of resins (dry climate) we found small quantities of organic phosphorous compounds (0.3-5 ppm) if these were applied as dust
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Screening Procedures for Organophosphorus, Organochlorine and Carbamate Pesticide Residues on Tobacco
Pages: 207 - 214
A method has been developed that permits the qualitative and quantitative determination of a number of chlorinated and phosphate insecticide compounds on tobacco. Extraction with acetonitrile, partitioning into petroleum ether, cleanup on a Florisil column are followed by gas chromatography and determination with the microcoulometric system (halogen) and the thermionic detector (phosphorus). A procedure is presented for the extraction and determination of the thiophosphates and water-soluble metabolites remaining in the acetonitrile-water layer after petroleum ether partitioning. Carbamate insecticides are extracted with methylene chloride, partitioned into water, separated by thin-layer chromatography, identified and estimated by colourimetry. Recoveries of the compounds (diazinon, parathion, Guthion, malathion, dimethoate) from tobacco fortified just prior to extraction ranged from 74 to 104 %; DDVP, Dipterex, Metasystox R 50 to 78 %, aldrin, DDT, lindane, thiodan 88 to 101 %, carbaryl, Unden 75 to 82 %, at levels of 0.5 ppm. The results for the field application of these 14 different insecticides on tobacco are presented. They show that there are nil or negligible residues from 8 organophosphorus and 1 carbamate insecticides (Unden); carbaryl and thiodan are well below the legal tolerances. Only the treatment of tobacco with lindane, DDT and aldrin (soil treatment) results in residues above the limit set
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Mass Spectrometric and Gas Chromatographic Evidence for Some New Components in the Gas Phase of Tobacco Smoke
Pages: 215 - 219
The gas phase of fresh tobacco smoke was injected onto an open-tubular gas chromatography column at low temperature. Mass spectra and retention data for components eluted on temperature programming suggest the presence of six new compounds: 1,1-, 1,2-cis-, and 1,2-trans- dimethylcyclopropanes; 1-chloro-5-methylhexane; 1,3,5-hexatriene; and 2-methyl-1-octene
- Accès libre
Pages: 220 - 228
A two-stage GLC system has been developed to produce a separation of cigarette smoke "semi-volatiles" into several hundred peaks per analysis. Quantitative measurements of the separated peak areas, with correction for baseline drift and an internal standard value, are made by an off-line computer, using a digital output obtained from the GLC system on punched tape. The main features of the computer program used are described, and typical output data are shown. Results of analyses dealing with cigarette smoke composition, and the selective effect of various filters, are presented. The use of neophytadiene as reference compound for the selectivity calculations is described
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Pages: 229 - 230
A pipe-smoking machine was constructed which simulates pipe-smoking. A photo-electric cell and a perforated endless belt were used for the time-regulation. The reproducibility of the puff and interval duration was fair: that of the crude and dry condensate of two types of tobacco smoked in this machine requires more investigation
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The Effect of Some Humectants on the Properties of a Flue-Cured Tobacco/Die Wirkung einiger Feuchthaltemittel auf die Eigenschaften eines röhrengetrockneten Tabaks
Pages: 231 - 238
1. The water-vapour transmission of four polyhydric alcohols has been determined for the products themselves as well as after a 3 % application on a flue-cured tobacco type. These polyhydric alcohols are glycerine, sorbitol, propanediol-1,2 and butanediol-1,3. The butanediol-1,3 shows the most hygroscopic properties.
2. Of the four products examined, the same butanediol-1,3 has the strongest fungistatic effect.
3. The taste of the cigarettes with butanediol-1,3 is better than that with sorbitol or propanediol-,1,2 (and diethyleneglycol).
4. The smoke nicotine content of cigarettes, the tobacco of which is treated with 3 % butanediol-1,3 is significantly lower than that of cigarettes out of the same type of tobacco with the other humectants or out of untreated tobacco. This can possibly be caused:
a. Partially by a relatively high moisture equilibrium of the tobacco.
b. Partially by a selective nicotine absorption in the butt (not in the filter).
c. Possibly there is still another effect, because the nicotine totals show a minimum with the glycol cigarettes. However, further experiments were not done.
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2nd Collaborative Study of the CORESTA on the Comparability of Three Selected Methods Measuring the Pressure Drop of Filter Rods/Auswertung der 2. CORESTA-Ringuntersuchung über die Vergleichbarkeit von drei ausgewählten Messmethoden für den Zugwiderstand von Filterstäben
Pages: 239 - 252
Nineteen companies and institutes participated in the second collaborative study, using the measuring methods VA, PA and C in 3 series of filter-rods of 50 pieces each; 4 participants received 3 series and 3 CFO respectively. The differences of the mean values were much smaller than in the first collaborative study and did not exceed 28 mm water. Also the standard deviation of the single values and the standard deviation of reproducibility have decreased to less than half in comparison to the first collaborative study. There was no difference in the method-mean value over all participants and series. Significant differences arose however between the participant-mean values and the mean values as well of the standard deviations of the participants as also of their standard deviations of reproducibility. A regression between the standard deviation of the single values and the standard deviations of reproducibility could however not be shown. Comparing the values of the standard deviation between the samples of the same participants to the values of the residual variance of the single analysis of variance of the series over all participants, it shows that the latter is mostly based on the systematic participant influence. Also a regression between the standard deviation of the single values and the mean values of the pressure drop could not be noticed. An influence of temperature, relative humidity and atmospheric pressure on the value of the pressure drop could only be stated in series III of measuring method C corr. But it was so small that it could practically be neglected. By means of a rank correlation a connection between the mean values of the first and the second collaborative study could be shown for different parameters with most participants. This fact is another proof that the stated differences in pressure drop are mostly based on factors being characteristic for the individual participants. It is to be aimed at the fact that all these factors are checked more thoroughly in order to improve the agreement of the mean values of the pressure drop between the participants
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Study on the Filling Differences in Cigarettes/Untersuchung über den fühlbaren Härteunterschied bei Cigaretten
Pages: 253 - 257
In several lots of cigarette samples the differences in hardness or filling of which had objectively been defined were estimated by a group of experts. The judgement was formed per pair of samples by the criteria ''harder" or ''softer". The part of correct answers was brought into a relation with the hardness or filling difference objectively determined. With the use of a logarithmic scale as basis for the hardness or filling difference, this relation was shown to be linear, which made it possible, based on all results of the experiment, to determine the threshold values of hardness for the capacity of differentiating sensorially. The authors are of the opinion that the described procedure is therefore capable of providing optimum results also in the case of similar problems, if the relation between sensorial judgements and objective measuring values is to be demonstrated